60" MXS V2__Three Year Endurance Test

I've written a lot about the 60 MXS over the past 10 years but every time I fly it, the plane still surprises me. I have a special attachment to the MXS for both practical and personal reasons.  First, it's one of the coolest and best flying planes ever, and secondly it has always suited me, especially the 60".  I had so many flights on my original V1 that the checkerboard covering started to blow off the tail! 

My dirty little secret is that my first 60" V2 had a short life. I forgot to rough up that battery tray and use alcohol to remove the mold release. On the second flight the Aura popped off the tray and it just went bonkers and strung itself through a chain link fence. It's mistakes like these that hurt the most because it was a stupid error you don't learn anything from. I can take biffing one on my own (which I do enough off), but to wreck a beautiful plane being so stupid was a waste at best.

Great. We got half a video of it. 

The problem was that these articles are time sensitive, and I had to get another one built and videoed in just another few days. I got another kit in two days, pulled a red eye and got it ready for the third day. We shot the video wrote the text and knocked the report out four days after the original crash. The V2 goes together so quickly that it wasn't a panic job or anything.  I enjoyed both builds, though admittedly I was extremely careful of every little detail when building the second.

 

MXS V2__Bad Attitude 03.mp4 from Doc Austin on Vimeo.

I took a lot of pictures simply because this is such a beautiful plane. I used Ben's recommendations from his build video, especially the part about the iron temperature when tightening covering. I stopped using paper towel to clean the plane and switched to micro fiber cloth. I use this for removing CA smears with debond or just cleaning the plane off with Windex. as you can see, this preserved the shine and after three years it still looks like it just came off the bench.

Here's Ben's excellent build guide.

    

FLYING

Nothing has changed here except the V2 is stiffer and more lively with the added benefit of being more precise. These were the first videos we could get with the second V2. I was still a little shook up from the crash and was determined to have a clean day, but once I got her in the air that disappeared and I could just get on with it. I'm very familiar with the MXS V1, so there were no surprised other than how much better locked in and lively the plane is.

The odd thing about the 60" MXS is it flies exactly like what you would expect from a scaled up 48" Extra EXP. That plane is my baseline and the one I compare all the other to, so not only was this a surprise, but it was a really good one. The plane flies exactly like what I have always been used to only bigger, better, more floaty and more precise. While the little MXS is a plane you have better know what you are doing with, the 60 V2 is more calm and composed, those it still winds itself up when you ask that from it.

In post stall it's very similar to the Extra, though a little livelier due to it's shorter moment. You also have more rudder authority, which helps in smoothing out a hover and also give you more authority in KE death slides and such,

As far as wing rock, forget about it. You have to get really sloppy to make this plane rock much. There's a very tiny rhythm in the way an MXS will rock, and it looks more like a deliberate little dance, with the plane not going off heading or dropping a wing too much.

Much like the Extra, the big MXS does such solid precision it's more like a pattern plane. Nice, long five second slow rolls are easy, with next to no coupling. It's not quite a graceful here as the Extra (but nothing is), but it's up to the pilot to bridge that gap and you can see for yourself in the videos just how well this plane tracks. Most pilots won't even notice the difference unless they work a lot of precision. 

For more detail, you can check our original Extreme Flight 64" MXS V2__Flight Report Extreme Aviation: Extreme Flight 64" MXS V2__Flight Report (docaustinextreme.blogspot.com)

Durability

There's not much to talk about here because the plane has survived three years of hard use without showing a mark of any kind. Part of this is I am so careful loading and unloading the plane, avoiding hangar rash, and finally, not ramming it through a chain link fence, and part of this is the V2 material is so tough. All my V1s flew and flew and flew with no failures of any kind, so I still expect the same sort of thing from the V2 only even better. They are strong, stiffer and lighter, and so far any V2 I have had in any size has been nearly bullet proof.

Three years is a long time for any aircraft, especially when they live on the deck. The fact this one is still like new points to the engineering and quality that goes into these planes.

MXS EXP Bad Attitude 2024 from Doc Austin on Vimeo.

Finally I usually send my V1s off into the sunset for one last video. This was the best sunset video I could find, though I have to admit the sky and the music really helped this one. The was shot using 6 volt servos, the standard Torque 4016 V2/Airboss 80 ESC, and no gyro. 

Finally, (last time) I put the MXS V2 into RealFlight, and these color schemes work with 3.5 to present.

MXS V2_Red_CS | RealFlight Forums

MXS V2__Green_CS | RealFlight Forums

Basic Set Up Tricks

Doc's note: This is not as comprehensive as Peter Goldsmith's excellent write up, but more a basic primer to help the new guys get the most out of their planes without overwhelming them. I'm a big believer in keeping things simple, and that's what I tried to do here.  I hope this gets you started well.

There's always a lot of confusion about set up. Your best friend is going to be experience, but if you get a decent basic knowledge that will take a lot of the fear, loathing and mystery out of what might seem like a black art. I know it's overwhelming because I went through it too, but hitting my set ups really helped me raise my game, and it didn't take that long for me to come to grips with it and get the most out of my planes.

Let's get the disclaimers  out of the way first. Set up can be an extremely personal thing, so there are no hard and fast absolutes. However, you'll get there faster if you start with a good baseline. The manual provides this. One exception for me was Extreme Flight's "insane rate." The new planes are so much livelier and more advanced they simply don't need it, and all that throw made the planes jumpier that I was after. So, now I just never put it on the plane, again a personal preference. If you want to spin the thing into orbit, have at it, but using just the low and 3D rates from modern manuals not only suits the new planes better, but they are easier to fly, more composed and make your flying smoother and more precise. 

When I started 3D the big throws scared me, so I tried to sneak up on it a little at a time. This blew up in my face with a plane that was too much for sport and not enough for 3D, essentially giving me a very badly set up plane. At Ben Fisher's urging I went back to the manual and got good results instantly. Remember, there is no such thing as "mild 3D." You either have enough throw for 3D, or you don't. You have a good flying plane or you have a pig, so don't discount the set up knowledge of the people who design and manufacture these planes.

Virtually every 3D plane I have flown that didn't fly right had a basic set up issue, so this article is meant to steer you away from that. I always tell my students that "Set Up is everything." 

I thought I would write up a little piece and outline how I do it. What's here is simply how I do it on my 48 and 60" planes, but it's very close to what is in the manual. I've adjusted a few things to suit how I like the plane to behave, but if you stick to the original Extreme Flight manual or 3DHS manuals, you can't go wrong.

Worth pointing out is the Extreme Flight set up is almost identical to the old pre-merger 3DHS manual. My guess is this is because it's what both companies found works best. Granted that's what I learned on and what I got used to, but the set up works on every 48-60" plane I have owned or set up for friends and customers.

Let's start with the set up from the 3DHS 47" Extra SHP. Most of us learned on this plane and are comfortable with it. It's capable but not overbearing.

Here's the numbers, and we will follow by breaking it down:

High/3D Rates (in degrees) and Corresponding Exponential

Aileron 28 degrees   75% Expo

Elevator 45 degrees   75% Expo

Rudder 45 degrees   75% Expo

Low/Precision Rates (in degrees and inches) and Corresponding Exponential

Aileron 15 degrees   30% Expo

Elevator 13 degrees   30% Expo

Rudder 45 degrees   75% Expo

Granted, this is just a starting point because you may like something different. Its a nice, safe set up that won't surprise or jump out from under you, but as you get experience you will learn to tailor it to make the plane suit you. 

I deviated a little here and there because the planes have become more capable, and on the low rate I deviate just a degree or two to give me a really good, smooth precision rate that suits me.

Worth noting here is expo values differ a bit from radio to radio. 75% on Futaba is roughly equivalent to 65% on Spectrum and Hitec, so if you fly those adjust accordingly.

You will notice I deviate from the manual just a little, but I will explain why I do this as we go along.

 

52 Slick EXP__Between The Stars from Doc Austin on Vimeo.

The 3D is the rate I use for everything except precision maneuvers. Expos values are different from radio to radio. I fly 75% on all channels, though for Spectrum that would be more like 65%.

3D Rate

ELEVATOR
I've found 45-50 degrees to be bang on perfect. The way most Extreme Flight and 3DHS planes are set up mechanically, you can get that 45-50 with your end points cranked and get the most resolution out of your servos. I don't understand this well enough to put it in writing other than you get a finer and less jumpy feel . It's sort of like a high resolution TV vrs a low resolution, The high res is a lot smoother, and finer. 

I like 75% expo, maybe because that's how I learned, but it still works. Remember, Spectrum would be about 65%.

AILERONS

Here I deviate from the manual just a bit because I believe I have improved my skills a bit since the SHP days. I usually go for 31-33 degrees because even that is barely enough to correct torque in a hover, but it's not so lively I can't keep up with it. Personally, much more feels jumpy, and I find myself overcorrecting, but 31-33 is what feels best to me.

RUDDER

Again, on most planes the elevator halves get in the way and won't allow much more than 45 degrees, and that seems about right. On some planes like the MXS, you can get a lot more, but I discovered that much rudder acted more like an airbrake and won't let the plane yaw correctly. Again 75 for Futaba and 65% for Spectrum users.

Low Rate

The low rate is a rate for precision flying, flying, but it is very, very similar to a sport plane. In fact, you can set the plane up with the low rate from the manual and you'll have a cracking good sport plane, maybe even better than the best sport planes.

Ailerons
Start with the low rate from the manual. From there I like to set my aileron rate to deliver three rolls in five seconds at full speed. The three in five used to be a maneuver from the old AMA pattern and it is just the right speed to roll the plane fast enough that all it takes to keep the plane level is a little elevator correction while not being so fast it's a struggle to keep up with and not so slow you get behind. You just bury the aileron stick and give it a gentle down elevator when it is inverted and a gently up when it's upright.

Elevator

Like the manual says, 15-20 degrees is nice and smooth. I've played with the expo a bit and discovered the manual seems to always be right.

RUDDER

You may notice the low and high rates are identical for the rudder. This works well because you have full throw for snaps and spins, while the big expo keeps things smooth for precision maneuvers.

So that was a lot of writing when all I really did was validate the manual. Worth noting is the 3DHS and Extreme Flight manuals are extremely similar, and my best guess this is because the set up works.

CG

Well, here's the source of a lot of unnecessary butthurt, but it's a lot simpler than all the talk would have you believe. Here's the secret: start at the front of the CG range specified by the manual, and this will be different from one airframe to the next. That's simply a starting point, but most people will be happy enough with that. I generally like to balance my planes a tiny bit nose heavy because that doesn't really sacrifice much 3D performance but does enhance high speed tracking and precision.

It is crucial to trim the plane first, and then follow the tests below I copy/pasted from the 3DHS 47" Extra SHP manual:

For this type of aircraft where I am going to predominantly fly aggressive 3D. I typically set the airplane up with a neutral CG, meaning that when the aircraft is flown inverted straight and level it requires no down elevator to maintain altitude. If your flying style leans more toward precision aerobatics then I recommend setting your CG using the 45 degree line test. Fly the aircraft from left to right or right to left, whichever direction you are more comfortable with at 3/4 to full throttle. Pull the aircraft to a 45 degree up line and establish this line and immediately roll the aircraft inverted. Establish this line and let go of the elevator stick. Ideally the aircraft will continue to track on that 45 degree line for several hundred feet before slowly starting to level off. Adjust the position of your battery to achieve this flight condition.

Plagiarism aside, I am aware I made this as simple as possible, but that is the point. I can't cite you all the aerodynamic theory that goes into it, I just know the manual works, I follow that and setting up CG is so simple it's been reduced to merely time consuming instead of black magic.

I like to mix a lot of precision in with my 3D to get a well-rounded presentation, so I like the roll over and 45 degree tests. If the plane flies upright and inverted trimmed, to me that's a little tail-heavy for what I am doing. Being just a tiny bit nose heavy locks the plane in and makes it track better, and if that sacrifices a little 3D it's not enough to notice.

Also my personal observation is every time I have not been happy with a plane, it was tail heavy, so I suggest starting at the front of the suggested range and slowly working back 1/4" at a time. Generally, the more you go back, the plane gets better, until it gets worse. I go for worse and then put the pack where I had it the last time I was happy with it.

Things I look for to avoid is a plane that won't trim on the elevator or won't do the same thing from one test to the next. That's usually an indication you are tail heavy. Conversely a nose heavy plane always flies nose heavy. Roll it over and if it drops like a pig you know you are nose heavy.

Eventually you will learn just how fast you want the plane to drop and how much you have to move the pack to make corrections, There is no easy path to this knowledge except lots and lots of stick time and experience. You not only have to learn to tune the plane, but also to get it to where you like it personally. This is why I tried to simplify the tests as much as possible.

A Set Up Snafu Of My Own Making
Below is an illustration of how much set up plays it's part in pilot confidence. My radio only has two rates, so I opted for low/insane. It's a Velox and it's supposed to be wild, right? The plane scared me a bit and I was not comfortable with it. The stability was there and the plane's most notable attribute, so I knew that, like everything else, that set up was the answer. I was going to get it right or bring it back in a bucket, and since I was uncomfortable, there was nothing to lose and everything to gain. I went back to the 3D rates, and this was the very first flight, in bad conditions no less, with the revised set up. This turned the Velox from a plane I was ready to give up on into one of the best planes I've ever had my hands on.

3DHS Velox__Doc Austin's Day Off from Doc Austin on Vimeo.

Mixes

Knife Edge Mix

For more advanced flying you need a plane that tracks like an arrow, even when it is on it's side. For example, in knife edge a plane can tuck toward or away from the canopy, so the best answer is to use a rudder (master) to elevator (slave) mix. For my style (or lack of), I start with a mix of 5% up elevator to left rudder and 3% to right rudder. That usually gets them really dialed in, but it is just a starting point because different CGs will react differently.

Look at it this way, when the plane is on it's side, the elevator, in relation to the ground, the elevator is acting more like a rudder because now that controls your yaw, and the rudder controls your pitch, in relation to the ground, that is. The ground is what you don't want to hit so it simplifies things to look at it that way.

If you are carrying any elevator trim, that will make the plane tuck either way. This is why you need to get the plane trimmed and balanced dead on before you get your mix set.

Other Mixes (In Progress)

There are also some other mixes I use to aid landing, but you can read about that here: Smoothing Out The 3D Landing

Once you get your plane died in, you might find a spolieron mix improves your harrier and elevator performance. Once you lean how to use it, it's quite  helpful, and you can read bout it here: Laser EXP__The Spoileron Files

For now I just wanted a basic primer to aid the new guys.  I'll add more stuff as I think about it some more, but hopefully you will find it helpful.